1. Field of the Invention
The exemplary embodiment relates to key mechanisms and, particularly to key mechanisms for portable electronic devices.
2. Description of Related Art
Key mechanisms of portable electronic devices, such as mobile phones, are usually formed on the sidewalls of housings of portable electronic devices.
FIG. 2 shows a typical key mechanism 10 including a key body 12, a resilient metal sheet 14, a circuit board 16, and a main board 17 connected to the circuit board 16. The resilient metal sheet 14 is positioned between the key body 12 and the circuit board 16. For comfortable touching, a soft film 18 is provided between the resilient metal sheet 14 and the key body 12, and adheres to the elastic sheet 14. The circuit board 16 has a first switch 162 and a spaced second switch 164. During pressing the key body 12, the soft film 18 deforms to electrically connect the resilient metal sheet 14 to the first switch 162 and the second switch 164.
However, the key body 12 is usually made of metallic material, which may generate static electricity. To remove the static electricity, a conducting layer 19 can be placed around the soft film 18, and the conducting layer 19 connects with grounding points 166 of the circuit board 16. Such arrangement increases manufacturing cost of the key mechanism.
Therefore, there is room for improvement within the art.